Fix the peer (I presume the network had to be OK for you to get this far.

Re-invites can be for, connected line updates, session-timers, or direct media. You can disable the first and last by using sendrpid=no and directmedia=no (previously called canreinvite). You can disable the middle one sufficiently to stop Asterisk initiating re-invites by using session-timers=refuse.